The present invention pertains to a video transmission device, a video reception device, and a video communication system.
As background art of the present technical field, there is e.g. JP-A-1998-308932 (Patent Reference 1). In the concerned publication, it is mentioned that:
‘“Problem’: To provide, in a data communication method, technology capable of carrying out video data error and loss recovery in addition to ensuring low delay characteristics and real-time characteristics.
‘Solving Means’: In a data communication method in which video data generated in real time node-to-node or end-to-end are communicated with high quality and in real time and taking a plurality of bundled communication packets to be a block, an acknowledgment reply including an ACK signal indicating that each of the transmission packets inside a block has been received correctly, or an acknowledgment reply including a NAK signal indicating that some transmission packet inside a block has not been received correctly, is generated in block units on the receiving side and returned to the transmitting side and, in the case where the acknowledgment reply in block units from the aforementioned receiving side includes a NAK signal, on the transmitting side, several of only those transmission packets for which retransmission is necessary are copied and retransmitted to the receiving side.”